Mechanical toothbrush



1964 J. R. AYMAR 3,

MECHANICAL TOOTHBRUSH Filed Feb. 8, 1963 3 Sheets-Sheet 1 INVENTOR. J UL/A N ROBERT A YMAR Dec. 15, 1964 J. R. AYMAR MECHANICAL TOOTHBRUSH 3Sheets-Sheet 2 Filed Feb. 8, 1963 INVENTOR.

JUL IAN ROBEQT AYMAQ omw w ATTOQA/EYS Dec. 15, 1964 J. R. AYMARMECHANICAL TOOTHBRUSH 3 Sheets-Sheet 5 Filed Feb. 8, 1963 INVENTOR.

JUL lAA/ ROBERT AYMAQ 6mm, k g w A TTOQA/f Y5 United States Patent3,150,902 MEEHANICAL TUG'IHERUEH .Iulian Robert Aymar, 2013 E. 67th St,Brooklyn, N. Filed Feb. 8, 1963, Ser. No. 257,239 8 (Ilaims. (CE. -42)This invention relates to a toothbrush and refers more particularly to abattery operated toothbrush for brushing the teeth in that mannerconsidered by dentists to be the mos-t effective movement to employduring brushing.

It is well known that dentists advise patients to brush their teeth withan up and down stroke of the brush to accomplish cleaning in the mosteffective way. This brush movement is not a truly up and down motion. Itis ratheran upward and downward oscillation of the brush head along itsaxis and relatively to the teeth. Many people, however, do not followthis advice and instead brush their teeth by moving the brush bristlesback and.

forth across the teeth. The latter while it may be a faster and lesscumbersome means of manipulating the toothbrush, is not totallyeffective for cleaning the teeth as it teeth with both a reciprocatingand an oscillating movement, thereby providing maximum cleaning action.

Still another object is to provide a mechanical toothrush which in useenables any person to brush his teeth in a correct and prescribedmanner.

A further object is to provide a mechanical toothbrush which is compactin size, light in weight and easily held in the users hand.

A still further object is to provide a mechanicaltoothbrush which has aremovable brush element thereby facilitating periodic replacement ofworn bristles.

Other obiects of the present invention will become apparent in thecourse of the following specification.

The aforementioned objectives of the present invention may be achievedby providing a mechanical toothbrush which has an elongated hollowcasing wherein may be supported a battery and a small electric motor.The electric motor drives a bevel gear pinion which drives a largerbevel gear, the latter being connected with a shaft supported rotatablyin the hollow casing. A brush rod is supported slidably in the casing atone end and extends outwardly therefrom. Connected to the extensionofthe brush rod is a brush element having a number of bristles carriedthereon. A crank pin isfirmly connected'at one end to the brush rod andextends perpendicularly to the axis of the brush rod, the other end ofthe crank pin extending into an eccentrically located opening in oneface of thelarger bevel gear. When the larger bevel gear is rotated, thecrank pin is moved in such manner that the brush rod reciprocatesaxially within the casing. Furthermore,the brush rodis. caused tooscillate so that the combined movement gives a proper brushing motionto the brush element.

The invention will appear more clearly from the following detaileddescription when taken in conjunction with the accompanying drawingsshowing, by way of example, preferred embodiments of the inventiveconcept.

In the drawings:

FIGURE 1 is a perspective view of a mechanical toothbrush: constructedin accordance with the principles of the present invention.

FIGURE 2 is a side elevational viewon enlarged scale of the mechanicaltoothbrush shown in FIGURE 1, one

, side of the casing having been removed.

' FIGURE 3 is atop plan. view of FIGURE 2.

v the bushing.

3,16%,9112 Patented Dec. 15, 1964 7 FIGURE 4 is a sectional view astaken along line IV- FIGURE 5 is a view in perspective of the conductor9 members and switch ring used for establishing continuity betweenthebattery and electric motor for starting and stopping the toothbrush.

FIGURE 6 is an end elevational view of the conductor members and switchring shown in FIGURE 5, the switch.

ring being shown in an on position. I

FIGURES 7 to 10, illustrate diagrammaticallythe relative positions ofthe brush rod during its reciprocating and oscillating movement causedby one complete revolution of the larger bevel gear.

FIGURE 11 is a perspective view of the battery charger and stand whereinthe mechanical toothbrush and'spare brush elements may be stored whennot in use.

FIGURE 12 is a longitudinal sectional view of a different embodiment ofthe toothbrush, as taken along a cutting plane passing verticallythrough they axis of the toothbrush casing.

FIGURE 13 is a side elevational view of the drive train of thetoothbrush shown in FIGURE 12.

FIGURE 14 is a top plan view of FIGURE 13. FIGURE 15 is a sectional Viewas taken along line XV-XV of FIGURE 13.

Throughout the specification, like reference numerals are used toindicate likeparts.

The mechanical toothbrush. 15) illustrated in FIGURE 1 comprises anelongated, generally cylindrically-shaped casing '11 having an opening12 at one end through which extends a brush rod 13 and on the end ofwhich is carried a brush element 14, the latter having a number ofbristles 15. A ring switch 16 encloses the casing 11 and is used forturning the toothbrush on and ofi. As seen in FIG- URE 1, the casing 11is made in two semi-cylindrical sections 1'7" and 18 which facilitatesassembly of the toothbrush and provides for easy breakdown when makingrepairs, etc. i Y

Referring now in greater detail to FIGURES 2 to 4, the toothbrush.includes a battery 19 whichis supported within casing 11 at one end. Inthis connection, the battery 19 may be a dry cell type, but ispreferably one of a re chargeable type as, for example, a nickel cadmiumbattery. A small electric motor 20 is supported in the casing 11 infront of the battery 19. A spring 21 is connected with the motor 28 andengages the battery 19. The electric motor 2i has a drive shaft 22 towhich is firmly connected a bevel type pinion gear 23. Casing sections17 and 18 have semi-cylindrical slots 24 and 25, respectively, whichextend in the sections substantially normal to the axis of the casing. Abushing 26 is supported in the slots 24 and 25 and a shaft 27 isrotatably supported within A large bevel type gear 28 is firmlyconnected with shaft 2'7 and meshes with pinion gear 23. As seen inFIGURES 4 and 7 to 10, the lower face of gear 28 contains'aneccentrically positioned opening 29.

Brash rod 13 which has an enlarged intermediate portion 3%, is supportedslidably in the casing 11 in an elongated cylindrically-shaped cavity 31which extends parallel to the axis of the casing. A crank pin 32 isfirmly connected with enlarged portion 39 of the brush rod and extendsperpendicular thereto. The crank pin 32 extends away from the brush rodand into the eccentric opening 29 in gear 23. Sleeves 33 and 34 enclosebrush rod 13 for supporti-m it within cavity 31.

The outer end 35 of brush rod 13 is substantially flat and fits in slot36 of brush element 14, this. beingthe means by which the brush elementis removably supported on the brush rod. As seen in FIGURES 4a and 4b,the brush rod 13 is provided with a rubber accordion type seal 55 whichencloses the rod and prevents water from entering the casing. The seal55 is supported on a boss like projection 60 surrounding the opening 12in the casing.

FIGURE 5 illustrates the means employed for turning the toothbrush onand off. A thin elongated conductor 37 is connected at one end with oneterminal of battery 19. The other end of conductor 37 is connected witha hoop-shaped conductor 38, the terminal ends 39 and 4% of which aresymmetrically arranged on each side of the casing near the bottom.Another thin conductor member 41 extends from a position between ends 39and 46 of hoop-shaped conductor 38 along the underside of electric motor29 and is connected to the motor housing. Ring switch 16 is an annularmember made from a nonconductive material. The inner face of the ringswitch carries an annular conductor segment 42.. The ring switch 16 isrotatable on casing 11 and is positioned thereon around the hoop-shapedconductor which also extends through and around the casing as shown inFIGURES 2 and 3. To establish continuity in the circuit, or to turn thetoothbrush on, ring switch 16 is merely squeezed on the casing 11 untilconductor segment 42 is brought into contact with and bridges the gapbetween conductor 41 and either the end 39 or the end of hoop-shapedconductor 38. This position is shown in FIGURE 6. To turn the toothbrushoff, the finger pressure on the ring switch is merely relaxed untilconductor segment 42 is out of contact with conductor 41. Spring 21 is,obviously, also one of the conductors used in establishing the circuit.

In operation:

Let it be assumed that the toothbrush It has been assembled, a brushelement 14 inserted on brush rod 13 and ring switch 16 properlypositioned on casing 11. Ring switch 16 is then squeezed so thatconductor segment 42 contacts and bridges the gap between either'end 39or end 40 of conductor 38 and conductor 41. This completes the circuitand current flows from battery 19 to motor 20. Motor drive shaft 22 willthus rotate driving pinion gear 23 which in turn drives bevel gear 28.As bevel gear 28 rotates, it imparts eccentric motion to crank pin 32.This motion of the crank pin is transmitted to brush rod 13 as acombined reciprocating and oscillating motion therein. This motion thusmoves vthe bristle carrying end of the brush element 14 in the preferredmanner for effectively brushing the teeth. In use, the user holds thecasing in one hand while the brush element is inserted in the mouth withthe bristles resting against the teeth. There is no need for the user tomanipulate the toothbrush except to move it from one tooth to next, etc.until all the teeth have been cleaned.

The brush element movement may be better understood by referring'toFIGURES 7 to 10 which'show the cyclic movement of the brush rod andwhich is the same as that occurring in the brush element. FIGURE 7 showsthe position A of bevel gear 28 at the start of one revolution, thecorresponding position B of the opening 29 and crank pin, thecorresponding longitudinal position C of brush rod 13 with respect to aselected longitudinal mark LM, and position D the end elevation of thebrush rod with respect to a vertical plane OM passing through the axisof the brush rod. After one-quarter revolution of bevel gear 28, theopening 29 is in position A, crank pin 32 in position B and brush tlOd13 has moved axially to the right beyond longitudinal mark LM.' At thesame time brush rod 13 has also rotated clockwise to position D (FIG.8). In FIGURE 9, or the'effect after one-half revolution, it is seenthat brush rod 13 has started to move in an opposite direction toposition C", while it also starts to rotate in a counterclockwisedirection. The positions A'", B, C, D' show this combinedreciprocation-oscillation movement as the bevel gear nears thethree-quarters revolution mark. Thus for each revolution of the bevelgear 28, brush rod makes one reciproeating stroke while at the same timeit undergoes one full period of oscillation.

FIGURE 11 illustrates a recharging stand 43 wherein the tooth brush itmay be inserted when not in use. The stand has an opening 44 forinserting the toothbrush, a contact 45 for recharging which engages arecharging conductor 46 connected with one terminal of battery l9 (FIG.2). Another contact (not shown) at the bottom of opening 44 contactsbutton conductor 47 connected to the other terminal of the battery 19.An electric cord 48 with plug 49 is used to connect the stand to asource of electricity for recharging the battery. The construction andoperation of the recharging stand is well known among those skilled inthe art. The stand 43 also includes a bank of vertical slots 50 forsupporting spare brush elements 14.

FIGURES 12 to 15 illustrate a somewhat different embodiment 76 of thetoothbrush. In this embodiment, the casing 71 is a hollow cylindricalmember with openings at both ends. A plug 72 is removably connected toone end of the casing 71 by means of screw threads 73. The plug 72contains a conductor 73 and has an annular shoulder 74 which is enclosedby an annular sealer ring 75. When the plug is screwed into the end ofthe casing, the sealer ring is urged into firm contact with the end ofthe casing and the annular shoulder 74 and thus acts as a seal toprevent water from entering into the casing.

A battery 76 is disposed concentrically within casing '71 and is used topower drive motor 77. The drive motor has an output shaft 78 to which isfirmly connected a spur type pinion gear 79. A support bracket 80isfirmly connected with the motor 77 and extends outwardly there fromand substantially parallel to the axis of casing 71. The support bracket80 serves to support rotatably a driven gear 31. The driven. gear 81 haspointed teeth 82 as shown in FIGURE 15 which due to their lesser lengththan the length of the teeth of pinion gear 79, mesh. adequately withthe pinion gear to provide a continuous non-slip drive between the twogears. It is preferable for sake of quiet running of the gears that thedriven gear 81 be of a synthetic material such as a soy bean compositionwhile the-pinion gear 28 be of metal. The upper face of driven gear 81is provided with an eccentric opening 82 wherein fits the crank pin 83on brush rod 84.

The same combined reciprocation-oscillation motor as was described forthe toothbrush 10 is thus imparted to the brush rod 84. An importantfeature of toothbrush 79 is that brush rod 34 is located to move alongthe axis of the casing 71. Furthermore, the crank pin 83 is located atthe end of the brush rod in contrast with toothbrush 10 wherein thecrank pin 32 is located intermediate the ends of brush rod 13.

The brush rod 84 extends through a central opening 85 in cap member 86which is firmly connected with casing 71. A number of metal sleeves 87and 88 are imbedded in the cap member 86 for supporting the brush rod. Arubber accordion type seal 89 is used to prevent water from enteringinto the casing 71. Brush rod 13 also carries a brush element 90. A pushbutton switch 91 of a type similar to those used on flashlights is usedfor turning toothbrush 70 on and oh. The wiring for toothbrush 70 is notillustrated inasmuch as'the same conductor arrangement illustrated inFIGURE 5 may be utilized for this embodiment.

Referring again to FIGURE 12 it was found advantageous to mount arectifier 92 Within plug 73. The rectifier is utilized in rechargingbattery 76 and is normally mounted in recharging stand 43 in a mannerwell known in the prior art. By mounting the rectifier in the toothbrushbody rather than in the recharging stand a considerable cost saving isobtained in making the recharging stand.

While there is above disclosed but some embodiments of the toothbrush,it is possible to produce still other embodiments without departing fromthe scope of the inventive concept herein disciosed.

What is claimed is:

1. A mechanical toothbrush comprising an elongated hollow casing havingan opening at one end, said opening being oifset with respect to thelongitudinal axis of said casing, a brush rod slidably supported in saidcasing and extending through and beyond said opening, a crank pin firmlyconnected with said brush rod and extending perpendicular thereto, agear having a plain lower face and an opening in said lower face locatedeccentrically with respect to the center of said gear, means forsupporting said gear in said casing for rotation in a plane parallel tothe axis of said casing, said crank pin extending into the eccentricopening in said gear, means for rotating said gear whereby said crankpin transmits reciprocating and oscillating movement to said brush rod,and a brush element carried by said brush rod.

2. A mechanical toothbrush comprising an elongated hollow casing havingan opening at one end, said opening being otfset with respect to thelongitudinal axis of said casing, a brush rod slidably supported in saidcasing and extending through and beyond said opening, a crank pin firmlyconnected with said brush rod and extending perpendicular thereto, abevel gear having a plain lower face and an opening in said lower facelocated eccentrically with respect to the center of said bevel gear,means for supporting said bevel gear in said casing for rotation in aplane parallel to the axis of said casing, said crank pin extending intothe eccentric opening in said bevel gear,

another bevel gear meshing with the first-mentioned bevel gear fordriving said first-mentioned gear, means for rotating said other bevelgear whereby the rotation of the first-mentioned bevel gear causes saidcrank pin to transmit reciprocating and oscillating movement to saidbrush rod, and a brush element carried by said brush rod.

3. A mechanical toothbrush in accordance with claim 1 wherein the meansfor rotating said other bevel gear comprises an electric motor supportedin said casing and having a drive shaft firmly connected with said otherbevel gear, and a battery for supplying electricity to said electricmotor.

4. A mechanical toothbrush in accordance with claim 3 further comprisingmeans for controlling flow of electricity from said battery to saidelectric motor.

5. A mechanical toothbrush comprising a cylindrical shaped casing havinga cavity extending from one end of said casing a distance in thedirection of the other end, said cavity being radially offset from, andparallel with the axis of said casing, a brush rod slidably supported insaid cavity and extending beyond the end of said casing, a crank pinfirmly connected with said brush rod and extending perpendicularthereto, a bevel gear having a plain lower face and an opening in saidlower face located ec centrically with respect to the center of saidbevel gear, means for supporting said bevel gear in said casing forrotation in a plane parallel to the axis of said casing, said crank pinextending into the eccentric opening in said bevel gear, another bevelgear meshing with the firstmentioned bevel gear for driving saidfirst-mentioned gear, an electric motor supported Within said casing andhaving a drive shaft firmly connected with said other bevel gear, abattery supported within said casing in alignment with said electricmotor for supplying electricity to said electric motor, said other bevelgear being adapted to rotate the first-mentioned bevel gear whereby saidcrank pin transmits reciprocating and oscillating motion to said brushrod, and a brush element carried by said brush rod.

6. A mechanical'toothbrush comprising an elongated hollow casing havingopenings at both ends, a plug removably connected to one end of saidcasing, an electric motor supported concentrically within said casingand having a drive shaft extending coaxially with the longitudinal axisof said casing, a battery supported in said casing for supplyingelectricity to said electric motor, a pinion gear firmly connected withsaid drive shaft, another gear meshing with said pinion gear, meanssupporting said other gear for rotation about an axis extendingperpendicular to the axis of said casing, said other gear having anupper face and an opening located concentrically in said face withrespect to the axis of rotation of said gear, a cap member firmlyconnected to the other end of said casing and having an opening thereinconcentric with respect to the axis of said casing, a brush rodsupported in said cap member and extending through and beyond theopening in said cap, a crank pin firmly connected at one end to saidbrush rod, and extending at the other end into the opening in said othergear whereby rotation of said other gear causes said crank pin totransmit a combined reciprocating and oscillating motion to said brushrod, and a brush element carried by said brush rod.

7. A toothbrush in accordance with claim 6 wherein said plug has acentral opening, and a rectifier supported in said central opening.

8. A mechanical toothbrush comprising an elongated hollow casing havingan opening at one end, a brush rod slidably supported in said casing, acrank pin connected with one end of said brush rod, the other end ofsaid brush rod extending through and beyond said opening, drive meansincluding a rotary driving member supported in said casing, said rotarydriving member having an eccentric opening therein for receiving saidcrank pin whereby said brush rod is reciprocated in the direction of itslongitudinal axis and oscillated about said longitudinal axis when saidrotary driving member rotates, and a brush element carried by said brushrod.

References Cited in the file of this patent UNITED STATES PATENTS1,869,991 White et a1 Aug. 2, 1932 1,945,616 Mastrud Feb. 6, 19341,965,382 Kluge -2 July 3, 1934 2,095,956 Bess Oct. 19, 1937 2,372,731Nalbach et al. Apr. 3, 1945 2,657,321 Smithson Oct. 27, 1953 2,977,614Demanuele Apr. 4, 1961 3,033,197 Barckley May 8, 1962

1. A MECHANICAL TOOTHBRUSH COMPRISING AN ELONGATED HOLLOW CASING HAVINGAN OPENING AT ONE END, SAID OPENING BEING OFFSET WITH RESPECT TO THELONGITUDINAL AXIS OF SAID CASING, A BRUSH ROD SLIDABLY SUPPORTED IN SAIDCASING AND EXTENDING THROUGH AND BEYOND SAID OPENING, A CRANK PIN FIRMLYCONNECTED WITH SAID BRUSH ROD AND EXTENDING PERPENDICULAR THERETO, AGEAR HAVING A PLAIN LOWER FACE AND AN OPENING IN SAID LOWER FACE LOCATEDECCENTRICALLY WITH RESPECT TO THE CENTER OF SAID GEAR, MEANS FORSUPPORTING SAID GEAR IN SAID CASNG FOR ROTATION IN A PLANE PARALLEL TOTHE AXIS OF SAID CASING, SAID CRANK PIN EXTENDING INTO THE ECCENTRICOPENING IN SAID GEAR, MEANS FOR ROTATING SAID GEAR WHEREBY SAID CRANKPIN TRANSMITS RECIPROCATING AND OSCILLATING MOVEMENT TO SAID BRUSH ROD,AND A BRUSH ELEMENT CARRIED BY SAID BRUSH ROD.